1. Field of the Invention
The invention relates to a side impact beam for integration into a vehicle door of a motor vehicle, wherein the side impact beam over at least the preponderant portion of its length has a profiled section with a hat-shaped cross-section comprising a stay and two leg portions, wherein the profiled section comprises a hook on an end section of the profiled section facing the door column, wherein the hook is angled toward the door column and engages an opening in the inner sheet metal of the vehicle door.
2. Description of the Related Art
Such a side impact beam is known from German patent document 296 22 985 U1. This side impact beam is provided at one end with a connecting tab that is bent upwardly from a planar end section. This connecting tab forms a hook and projects into one of the door columns of the vehicle body when the door is closed. The hook is designed to provide, in addition to the door lock connection of the vehicle door, a second positive-locking connection and to provide an additional safety feature in the case of a side impact. A weak point of this known design is, however, the planar end section which can buckle or break off upon side impact. Also, the hook is not sufficiently bending resistant. The hook can therefore fulfill its function only to a limited extent. A desired higher lateral rigidity as well as safety is thus achieved only to a limited extent.
It is an object of the present invention to provide a side impact beam which is improved with regard to its function and which ensures a more stable connection to the door column in a load situation.
In accordance with the present invention, this is achieved in that the hook has a hat-shaped cross-section and is arranged at the end face of the end section which has a decreasing height.
Accordingly, the hook has a hat-shaped cross-section and is arranged at the end face of the end section which decreases in its height. The hat-shaped cross-section extends from the middle section of the profiled section across the end section wherein the height of the end section, starting at the middle section, decreases toward the end face. The end section then has a transition into the hook, i.e., the end section and the hook form a unitary part.
The side impact beam according to the invention is configured in an optimized fashion with regard to loading. It has a profile of continuous thickness from the center to the end without easily bendable areas.
When the door is closed, the hook provides a stable second positive-locking connection to the door column. An increased lateral rigidity and thus an increased energy absorption in the case of a side impact are thus ensured.
The side impact beam according to the invention can be used in front doors as well as rear doors. The hook engages accordingly either a cutout in the B column or in the C column of the vehicle body.
According to a further embodiment of the invention, the hook has a thickness that is increased relative to the remaining portion of the side impact beam. Accordingly, the general strength and flexural strength can be further increased in the connecting area. Preferably, the thickness of the sheet metal in the end section relative to the sheet metal of the remaining profiled section is greater by a factor 1.5.
The reinforcement of the hook area can be realized by using a blank sheet metal which at one end has a sheet metal portion which is thicker in comparison to the remaining sheet metal area. Such sheet metals are also referred to in the art as tailored blanks.
Possible is also the use of so-called patchwork blanks in which at the hook-side end at least one further sheet metal is connected in a sandwich construction. The hook is then of a double layer construction. The double layer construction is realized preferably by folding the sheet metal in the area of the end section. This is advantageous with regard to manufacturing technological considerations.
According to a further preferred embodiment, transversely projecting flanges are provided on the leg portions of the profiled section. This feature also enhances the flexural strength of the side impact beam and the denting resistance of the door in an advantageous manner. The flanges extend along the end sections up to the hook. They widen along the end sections at least over portions thereof. This configuration makes possible a stable securing of the side impact beam on the inner sheet metal of the door, preferably by spot welding. Moreover, by widening the flanges the strength of the end section at the hook is increased. In a preferred embodiment, the hook also has lateral flanges.
For reasons of corrosion protection and of safety, the hook is provided with a plastic cap. This measure also improves the visual appearance.
The side impact beam according to the invention is formed of super high strength sheet metal that is cold and hot formable. Moreover, it is provided with a surface protection, for example, by hot galvanizing or electro-galvanizing.